Device for conditioning and sharpening implements



Oct. 25, 1938. R. T. CDONALD 2,134,339

DEVICE FOR CONDITIONING AND SHARPENING IMPLEMENTS Filed Sept. 25, 1935 INVENTOR 'ATTORNEYS Robert T. M Donald.

Patented Oct. 25, 1938 DEVICE FOR'CONDITIONING ANn SHAIt PEN- ING IMPLEMENTS r RobertiT. McDonald, Hornell, N. Y., assignor of 'qne-half'to Eugene E. Grimm; Franklin, Pa. 1

Application September- .25, 1935 Serial No. 4.21mi:

' a '3 Claims. (01. 51 "'204 which is adapted to be used either'as a-surface conditioner for knife sharpeners or as a sharpening tool for blades, or thelikep One object of the invention is to provide an improved surface conditioner-for metal knife;

sharpeners. I 7

Another object of the invention is-to provide an improved surface conditioner for knife sharpeners which is also so constructed as to serve as a sharpener for metal blades. 5

The invention is exemplified in an arrangement of a plurality of abrasive sections surrounding a central opening through which a-blade sharpener can be inserted and reciprocated, or oscillated, or otherwise frictionally forced against the inner surfaces of the sections to recondition or roughen the sharpener surface. The sections are resiliently held together in assembled relation and are of such length as to be adapted for manual operation by an operator holding the conditioner in one hand and the sharpener in the other. The opposed faces of the sections are provided with beveled converging surface portions which are adapted to receive an edge of a blade for sharpening the latter by proper manipulation thereof.

In the drawing:

Fig. 1 is a perspective of an abrasive conditioner in an operative position in connection with a sharpening tool;

Fig. 2 is a perspective of the principal elements of the improved device and shown in disassembled relation;

Fig, 3 is an end elevation of the conditioner and illustrating a different form of device for maintaining the elements thereof in assembled relation;

Fig. 4.- is a perspective of the conditioner as it is used for sharpening a knife; and

Fig. 5 is a cross section taken substantially along the line VV of Fig. 4.

In practicing the invention a conditioner l0 is constructed of complemental sections l2 preferably oblong in form and they are provided with normally abutting surfaces [5 which can be held in proper non-shifting, but in separating, relation by means of dowels I6 provided on one face I 5 for loosely fitting into openings 1 I in the other face. Opposed channels l8 are formed centrally along the abutting faces of the sections l2, and in the assembled relation of the sections these channels constitute an axial passage extending entirely through the conditioner l0.

:Opposed faces of the sections [2 adjacent one end of the conditioner are beveled, as indicated at l9, and when the faces [5 are in abutting relation to each otherthe opposed beveled portions of the sections define cusp-shaped crevices 20 (Fig. 5), wherein the innerportions of the surfaces defining them converge into substantlalj contact with each other. .v

In order to maintain the sections I2 in assembled relation the outer circumferential section surfaces are grooved, as indicated'at 22, to forma seat for a resilientband 23 encircling the conditioner'andnormally under tension. This band canbe' inthe form of endless elastic-material, such asrubber, or it can be in the form of a resilient metal strip, or ring 24 '(Fig. 3). rubber band is used the dowels l6 prevent longitudinal relative shifting movement of the sections in axial directions. When a metalband is employed the dowels can be dispensed with because the band seated in the groove portions 22 prevent such shifting of the sections.

In Fig. 3 the resilient metal band 24 is sinuous or corrugated and endless. The corrugations 25 of the band 24 permit the band to be expanded in order that it can be slipped over the sections and seated in the grooved portions 22 thereof. The band can also be in the form of a split ring or band 26 havinga bent portion or lug 21 that is normally positioned in one of the crevices 20 to prevent circumferential shifting of the ring, and its end portions are outwardly turned slightly to form. finger pieces 28 for the purpose of facilitating the manual manipulation thereof. Since the end portions 28 are disposed adjacent the crevice 20, the operators fingers can more conveniently engage them for removal of the ring, when such operations are desired.

The sections l2 are composed of coarse grained abrasive material, such as carborundum, and can be cast, moulded, or otherwise shaped into the form shown.

A sharpening tool 30, for example, the kind commonly used in sharpening knives is inserted through the axial opening formed by the channels I8 and. the spreading of the sections is resisted by theresilient band as the tool is inserted. By holding the conditioner with one hand and manipulating the sharpening tool with the other, this tool can be roughened-or serrated by frictional engagement of the inner surfaces of the section upon the outer surface of ing the tool frictionally through it in an axial When a.

direction for the purpose of roughening or upsetting the tool surface in more than one direction.

The conditioner 10 can also be employed as a sharpener, and in this connection the cutting edge32 of a knife 33 can be inserted in either crevice 20 and drawn back and forth, or repeatedly drawn in one direction, untilthedesired sharpness is secured. It is tobe':-understood that the conditioner can be anchored while the conditioning or sharpening operations are.

being accomplished, or the conditioner can be" held in the hand of the operator,andsp ressurerv appendedclaims;

I claim: 1; A-;devi'ce foriconditioningabladesharpeners 30 I comprisingra; plurali-tmof oblonggcontiguous segi ments, recessed: longitudinalhn in: their, opposed; faces: to: form-t. a5; longitudinal opening: them; through; projections: andz-zopenings .beingiformeds on: .thempposecliaces g-of-w the segments andgnor+-- mally engaged'in lloosely: interfittingirelation to; maintain the. segments. against relative.- longi-.- tudinal. movement-resilient means= constitutingr the sole support; for said segments and:

yieldably maintaining the segments in opposed assembled relation, the surfaces of the segments defining the opening being composed of abrasive material for upsetting the surface of a sharpening tool frictionally forced through the opening.

2. A device for conditioning blade sharpeners comprising a plurality of segments of abrasive materialf recessed to form an opening surrounded by the segments and passing therethrough, re-

.silient means for yieldably maintaining the segments in assembled relation, the surfaces of the "abrasive" materialdefining the opening being formeditb embrace a metal sharpening tool and to upset thesurface. of the latter upon forcing it throughfthe' opening, opposed segment portion's'adjacentthe"extremities of the segments having:-convergingibeveled surfaces for receiving and sharpening a knife blade.

3;" A'device for conditioning a blade sharpener com-prising; azpluzality, of oblong contiguous segments recessed i1 longitudin-ally; of their opposed faces-to 'formi a longitud-inal opening through the:

device eadjacen-t portions of adjacent segments beingbeveledctosform; v shaped crevices, axresi1-= ient split ring circumferentially -engaging the-as-' sembledrsegments and havinga projection disposed; ineone ot .the crevices :to prevent circumferential shifting of the ring, the split. portion. OfnthCHF-iflfi; being; disposed .adjacent :another one of: theecrevices to? facilitate: removal: of thering. from the:segxnents,-;thetsurfaces of. thersegments: defining the openings being: composed of abra.

sivei; material for upsetting; the surface of 'a.

sharpening tool uponfrictionally forcing the; tool through saido ni {ROBERT-Fr; MCDONALD. 

